Frame aerial



Sept. 29, 1942. FUNKE HAL 2,297,466

. FRAME AERIAL Filed Jan. 2 6, 1940 1 2 Sheets-Sheet 1 Sept. 29, 1942.

w; FUNKE E.T AL

FRAME AERIAL Filed Jan. 26, 1940 2 Sheets-Sheet 2 Patented Sept. 29, 1942 FRAME AERIAL Walter Funke, Berlin, Bruno Kalz, Dabendorf,

and Helmut J oh'anns'on, Berlin, Germany; vested in the Alien-Property Custodian Application January 26, 1940, Serial No. 315,720 In Germany April 24, 1935 7 Claims.

In order to obtain bearings with respect to a radio transmitter and to obviate disturbances in the reception of the signals therefrom frame aerials are employed, as is well known in direction finding systems.

The invention has for its object to increasethe efficiency of such arrangements and for this:

purpose provides forincreasing the intensity of reception by means of an iron core arranged'to collect the lines of force of the field in which the aerial is moving. Preferably, such core should be made of finely divided ferro-magnetic material, that is, the so-called high frequency iron, this having been much improved recently.

In the accompanying drawings, Fig. 1 is a perspective diagrammatic view that serves to explain the idea of the invention. Fig. 2 is a view similar to Fig. 1 and illustrates a slight modification of the arrangement there shown. Fig. 3 is a sectional elevation representing a constructional form of an aerial as provided by the invention. Fig. 4 is a plan view of the arrangement shown in Fig. 3. Fig. 5 is a sectional elevation representing this arrangement as fixed to an aeroplane. Fig. 6 shows a section on line "6-6 of Fig. 5.

The arrangement represented in Fig. 1 comprises a frame aerial R and a hollow cylinderZ, located therein and made of high frequency iron.

This cylinder instead of being hollow may be a solid body.

In the case of Fig. 2 the iron core Z is a solid body enlarged at its ends in order to collect and convey to the aerial R as many lines of force as possible.

The result so obtained is in a sense the reverse of that obtained in the case of high frequency coils provided with an iron core. In the latter case the iron core serves to diminish the magnetic leakage, whereas in the case of the novel arrangement the high frequency alternating flux passing through the frame area is increased more or less as compared with the same frame not fitted with an iron core, such increase depending upon the leakage of the core. In this way it will be possible to reduce the frame area without affecting the intensity of the receiver input circuit. The aerial may thus be made to present a comparatively small resistance to air and will hence be suitable for use on board aircraft, for instance.

In order also to reduce the weight of devices as provided by the invention the constructional forms thereof described hereafter have the iron core made in the form of a hollow body.

The

- airplane.

core may be hollow because, as has been found by experiment, the inner material thereof does not substantially increase the number of lines of force passing through the frame aerial. Prefer-' ,ably, the core is a rotational body in the shape of a truncated cone in order to lessen its 'resistance to air, aswill be understood from the following description which refers to Figs. 3 to .6.

The hollow iron core 1 shown in Figs. 3, 4, 5 is composed of an upper part or cap land a base plate 4 fixedly connected therewith. This core is mounted on a vbaseplate 2 by means of plate 4. Part 3 is substantially in the shape of a truncated cone whose axisIAA extends along the planes of windings 5, 5' which constitute the aerial. Core I is in this way formed as flat as possible, its resistancetoair thus being minimized. The windings 5, 5 are located in grooves recessesi, 6 of the core I.

In the present case, represented vby way of example, two such windings are offset at'right angles with respect toeach other. One of these windings is the finding aerial proper, serving to determine the position of the courseline, while the other winding, intended to .find the direction or so-called side in that line, is to be connected in its turn with the input circuit of the receiver, that is, connected therewith instead of the former winding. Plate -2 carries plug pins 1 by means'of which the deviceshown in Figs. 3 and 4 is attached to a current-collecting .de-. vice provided in-an air-plane, for example, as will be understood from Figs.-5 and-6.

B, Fig. 5, denotes part of the outer wall of the In an opening of this wall a casing 8 is secured thereto, as by screws, for instance. Located within casing 8 is a, disc 9 carried by three rolls Ill which are mounted in this casing. Disc 9 is formed integral with a worm wheel II. The worm l2 arranged to engage therewith is connected. with a flexible shaft or is electrically remote controlled. Disc 9 has a central opening and this is covered by a plate I3 rigidly fastened to the disc 9. In the plate I3 contact sleeves l4 for the plug pins 1 are fastened. These sleeves are connected to contact rings l5 by conductors ll. The casing 8 has contact brushes [6 rigidly mounted therein and arranged to cooperate with the rings IS in order to collect the currents received by the windings 5, 5'.

The assembly 1, 2, held in place by the plug joint 1, [4, may in addition be secured to the disc 9 by screws, for instance, such as hinged screws distributed along the edge of this disc. This feature is not shown in the drawings.

A cap I8 is arranged to protect the device from wind and weather conditions.

Core I may be formed of component parts and in a manner to minimize the reluctance.

The frame assembly I, 2, 5, instead of being rotatable, as shown, may be fixed in an unvariable position in order to serve for the so-called aim-flight of airplanes.

What is claimed is:

1. A directive radio receiving arrangement adapted to be mounted on a wall of an airplane and comprising a loop antenna of substantially uniform cross sectional area open at its ends, and a truncated core of soft iron material arranged within said loop antenna and confining the latter peripherally thereof and extending beyond the ends thereof and said core having a base portion sustained by said wall.

2. A directive radio receiving arrangement adapted to be mounted on a wall of an airplane and comprising a loop antenna of substantially uniform cross sectional area open at its ends, and a hollow truncated core of soft iron material arranged within said loo-p antenna and extending beyond the ends thereof and comprising a base portion sustained by said wall.

3. A directive radio receiving arrangement adapted to be mounted ona wall of an airplane and comprising a loop antenna of substantially uniform cross sectional area open at its ends, and a rotational hollow core of soft iron material extending within and beyond the ends of said loop antenna, said core having a base portion sustained by said wall and a hollow cap portion secured to said base portion, said base and cap portions having recessed means, said loop antenna including windings disposed in said recessed means, the planes of said windings being substantially parallel to the axis of rotation of said hollow core.

4. A directive radio receiving arrangement adapted to be mounted within an opening in a wall of an airplane and comprising a loop antenna of substantially uniform cross sectional area open at its ends, a truncated hollow core of soft iron material arranged within said loop antenna and extending beyond the ends thereof, said core having a base portion sustained by said wall and a tapered cap secured to said base portion, said cap and base portion having recessed means disposed substantially normal to each other and said loop antenna having substantially flat windings disposed in said recessed means.

5. A directive radio receiving arrangement adapted to be mounted on a wall of an airplane and comprising a loop antenna of substantially uniform cross sectional area open at its ends, a hollow truncated core of soft iron material arranged within said loop antenna and extending beyond the ends thereof and comprising a base portion sustained by said wall and a hollow tapered top portion secured to said base portion, said base and top portions including intersecting recesses extending along the outer surfaces thereof, said loop antenna comprising windings disposed in said recesses, and electrically controlled means for energizing said windings.

6. A directive radio receiving arrangement adapted to be mounted on the wall of an airplane and comprising a loop antenna of substantially uniform cross sectional area open at its ends, a hollow truncated core of soft iron material arranged within said loop antenna and extending beyond the ends thereof and comprising a base portion sustained by said wall and a hollow tapered top portion secured to said base portion, said base and top portions including intersect ing recesses extending along the outer surfaces thereof, said loop antenna comprising relatively fiat windings in said recesses, electrically controlled means for energizing said windings, and adjustable means for rotatably displacing said core relative to said wall.

7. A directive radio receiving arrangement adapted to be mounted in an opening of a wall of an airplane and comprising a loop antenna of substantially uniform cross sectional area open at its ends, a hollow truncated core of soft iron material arranged within said loop antenna and extending beyond the ends thereof and comprising a base portion sustained by said wall and a tapered top portion secured to said base portion, said base and top portions defining a truncated body including peripherally disposed and intersecting continuous recesses extending along the outer surfaces of said body and arranged substantially normal to each other, said p antenna comprising relatively flat windings disposed in said recesses, electrically controlled means for energizing said windings, means rotatably sustaining said core, and adjustable means for actuating said means rotatably sustaining said core.

WALTER FUNKE. BRUNO KALZ. I-IELMUT JOHANNSON. 

